1. Field of the Invention
The invention refers to assemblies that include a gliding board and a device for retaining an article of footwear.
Such assemblies are adapted for the practice of sports, such as cross-country skiing, telemark skiing, downhill skiing, and any other kind of skiing, as well as snowshoeing, and the like.
2. Background Information
In the assemblies of the aforementioned types, the retaining device extends longitudinally, from a rear end to a front end, the board having a receiving zone provided to receive the retaining device longitudinally. Thus, when operating the board, a user can apply supporting forces, exert pushing forces, return forces, guiding forces, and other.
This translates into the transmission of steering impulses and sensory information for each board, as well as in the retaining device and the boot which are associated therewith.
An example comes from cross-country skiing. In this case, the boot is retained by the tip, the heel being free to move alternately away from and toward the board.
In the case of skating steps, the user applies lateral pushing forces and forward return forces alternately with each leg. During the lateral push, the ski is pressed flat on the ground and glides obliquely in relation to the advance direction. The pushing force is efficient when the ski glides without skidding. This is where efficiency is the highest, as all of the energy related to the push moves the user forward. However, this is not always the case, in the sense that the ski skids sometimes, and that efficiency is negatively affected. The same is true during a forward return of the ski during such skating steps. An interference occurs sometimes between the ski and the ground. For example, if the ski is not sufficiently parallel to the ground, one of its ends can drag on the ground. This negatively affects steering efficiency, causes unnecessary fatigue, and can even throw the user out of balance.
When using alternate steps, also known as classic skiing, the skier alternately thrusts each ski forward, and then takes vertical support by pushing, or applying an impulse, towards the ground, in a repetitive fashion. During a thrust, one ski glides longitudinally on the ground, in the forward direction. The thrust is efficient when the ski glides evenly, without jerking. This is where efficiency is the greatest, as the energy related to the thrust moves the skier forward. However, this is not always the case. Sometimes, the ski undertakes a short backward travel, or the advance is simply shortened in relation to the maximum possible.
When vertical support is being taken with one leg, the ski is pressed flat on the ground, which makes it possible for the skier to move the other leg forward. The support is stable when the ski, on which the impulse is applied, does not move backward while the other ski is being moved forward. This is where efficiency is increased because the length of the strides tends towards the maximum possible. However, it appears that this is not always the case. Sometimes the ski, biased towards the ground moves backward against the skier's will. This negatively affects the steering efficiency.
Steering efficiency is also negatively affected sometimes when operating snowshoes. As with cross-country skiing involving alternate steps, the length of the stride is reduced in relation to the maximum possible, or a snowshoe in support moves backward against the skier's will.
In downhill skiing, where the boot is retained at the front and back, the skier has to be laterally supported on the running edges in order to manage his/her path. The skier's path is all the more precise as each running edge glides without skidding. A lateral support force must thus be applied as firmly as possible to make it easier for a running edge to penetrate in the snow. Again, it appears not always to be the case. Sometimes, the board, in this case the ski, skids against the skier's will. The loss of energy resulting from undesired skidding negatively affects the steering efficiency.